This invention relates to triggering circuits for triggering the operation of remote systems.
More particularly, the present invention relates to a triggering circuit dependent on light.
There are many systems today, such as automobiles, computers, financial systems, etc. which, for security reasons, require limited or authorized access. Many of these systems operate with keys, cards, etc., which can often either be duplicated or bypassed. It would be advantageous to not only gain access to the system using these devices, but also to provide additional security in the form of a trigger which will actuate the operation of a system upon specific conditions.
Often, access to systems is regulated by very costly and complicated security systems which require coding and comparisons using expensive processing units. For example, security doors include a magnetic strip reader which collects a code from a magnetic strip. The code is compared by a processing unit to stored codes, and then, depending upon the comparison, the processing unit initiates certain activities such as operating the door opening system. Due to the high cost of these security systems, security is often ignored on simple low cost systems.
Additionally, most security systems require an individual""s actual presence for operation. For example, a key card is used at a door to open that door. However, it is often necessary to operate remote devices in a secured manner. Currently, this is not taught by the art.
It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
Accordingly, it is an object of the present invention to provide a new and improved trigger circuit for triggering a remote system.
Another object of the present invention is to provide a trigger circuit to enhance security and/or identification in a remote system.
And another object of the present invention is to provide a trigger circuit which is relatively less costly and can be economically employed on even the simplest remote systems.
Briefly, to achieve the desired objects of the instant invention in accordance with a preferred embodiment thereof, provided is a trigger circuit including a light source supplying a first beam of light having a first frequency, a frequency altering device positionable to receive the first beam of light. The frequency altering device receiving the first beam of light and transmitting a second beam of light having a second frequency. A frequency sensitive component operable in response to the second beam of light having the second frequency, the frequency sensitive component being positioned to receive the second beam of light and provide a trigger signal. A trigger coupled to receive the trigger signal and, upon receipt of the trigger signal, triggering the system.
In a specific embodiment the frequency sensitive component includes a photo-transistor, a potentiometer and a JFET coupled to the photo-transistor to adjust the component to be sensitive to the second frequency. The frequency sensitive component can further include a light filtering device which transmits only the second beam of light with the second frequency. The light filtering device is positioned to receive the beam of light from the frequency altering device and the photo-transistor is positioned to receive the second beam of light from the light filtering device and provide a trigger signal in response thereto.